Danfoss VLT FC 100 Series Programming Manual page 180

Parameter Description
23-67 Reset Timed Bin Data
Option: Function:
Select Do reset [1] to reset all counters in
23-62 Timed Bin Data.
After pressing OK, the setting of the parameter
value will automatically change to Do not reset
[0].
[0] Do not reset
[1] Do reset
3.21.5 23-8* Payback Counter
The Adjustable frequency drive includes a feature which
can give a rough calculation on payback in cases where
the Adjustable frequency drive has been installed in an
existing plant to ensure energy saving by changing from
fixed to variable-speed control. Reference for the savings is
a set value to represent the average power yielded before
the upgrade with variable-speed control.
Figure 3.65
Parameter overview:
Parameter for settings
Rated Motor Power
Power Reference Factor in %
Energy Cost per kWh
Investment
Table 3.31
23-80 Power Reference Factor
Range: Function:
100 % [0 - 100 Set the percentage of the rated motor size
*
%] (set in 1-20 Motor Power [kW] or 1-21 Motor
Power [HP]) which is supposed to represent
the average power yielded at the time
running with fixed speed (before upgrade
with variable speed control).
Must be set to a value different from zero to
start counting.
®
VLT HVAC Drive Programming Guide
1-20 Motor Power [kW]
23-80 Power Reference Factor
23-81 Energy Cost
23-82 Investment
MG11CD22 - VLT ® is a registered Danfoss trademark
The difference between the Reference Power at fixed
speed and the Actual Power yielded with speed control
represent the actual savings.
As value for the fixed-speed case, the rated motor size
(kW) is multiplied with a factor (set in %) representing the
power produced at fixed speed. The difference between
this reference power and the actual power is accumulated
and stored. The difference in energy can be read in
23-83 Energy Savings.
The accumulated value for the difference in power
consumption is multiplied with the energy cost in local
currency and the investment is subtracted. This calculation
for cost savings can also be read in 23-84 Cost Savings.
Cost Savings =
{
t
(
∑ Rated Motor Power ∗ Power Reference Factor
t =0
Actual Power Consumption
−
Investment Cost
−
Break even (payback) occurs when the value read in the
parameter turns from negative to positive.
It is not possible to reset the Energy Savings counter, but
the counter can be stopped any time by setting
23-80 Power Reference Factor to 0.
Parameters for readout
Energy Savings
Actual Power
Cost Savings
23-81 Energy Cost
Range: Function:
1.00 [0.00 - Set the actual cost for a kWh in local
*
999999.99 ] currency. If the energy cost is changed
later on, it will impact the calculation
for the entire period.
)
}
Energy Cost
×
23-83 Energy Savings
16-10 Power [kW], 16-11 Power
[hp]
23-84 Cost Savings
3-153
3 3